Lightening every few seconds!! Why?

I saw a flash out the window n told my boyfriend.. He looked out and was fasinated!! He said he'd never seen lightening like this n it flashing so much!.. He says something is cookin up.. I hope he means just a small storm :( i hate things like this, so im quite scared! Im sittin in the livin room watchin tv while he sittin in bedroom starin at it.. Is it just a storm (theres no rain yet) why is the lightening flashes every few seconds??..